April 22 – The first of the Statutes of Westminster are passed by the Englishparliament, establishing a series of laws in its 51 clauses, including equal treatment of rich and poor, free and fair elections, and definition of bailable and non-bailable offenses.
Eleanor de Montfort is captured by pirates in the employ of Edward I of England to prevent her marriage to Llywelyn the Last, prince of Wales; she is used as a bargaining chip over the coming years in Edward's attempts to subjugate Llywelyn and Wales.
Scottish forces defeat the Manx of the Isle of Man in a decisive battle, firmly establishing Scottish rule of the island.
Jean de Meun completes the Frenchallegorical work of fiction, Roman de la Rose, with a second section; the first section was written by Guillaume de Lorris in 1230.
The verge escapement, a simple type of escapement used in clocks, is invented (exact year unknown).
The first main survey of the Hundred Rolls, an Englishcensus seen as a follow up to the Domesday Book completed in 1086, is finished; it began in 1274.
Asia
March – the 200,000 multiethnic troops of the Mongol-led Yuan Dynasty, headed by the Turkish commander Bayan, face a ChineseSong Dynasty army of 130,000 led by the Song Chancellor Jia Sidao. The result is a decisive victory for the Yuan Dynasty, and soon after the much-vilified Jia Sidao is stripped of rank and title, and killed by one of his own guards as he is sent to exile in Fujian by the Song court.